In the upcoming season, Dexter may face his fiercest opposition yet: RoboCop. Peter Weller, who assumed the title role RoboCop franchise, has joined the cast of Showtime’s Dexter for season five. According to Deadline, he will play “a troubled Miami Metro police officer who gets caught up in an internal affairs investigation.” The veteran actor — most recently seen in a guest spot on the third season of Fringe — joins Julia Stiles as a new addition to the cast.

Hit the jump for details on The Wire alum Aidan Gillen’s role in the HBO fantasy series Game of Thrones, and who might replace Melina Kanakaredes as she departs CSI: NY.

According to The Live Feed, Gillen has signed on to play Littlefinger in HBO’s adaptation of the George R.R. Martin series A Song of Ice and Fire. Here’s a brief logline for the first season:

The sprawling tale set in the mythical land of Westeros tells the story of the noble Stark family who become caught up in high court intrigue when patriarch Eddard (played by Sean Bean) becomes the king’s new right-hand man.

The series is in the midst of reshoots, and sadly won’t have a trailer ready for its ideal venue, Comic-Con 2010. However, HBO remains confident it can premiere Thrones as early as next spring. To nail the adaptation of such a sprawling fantasy series will simply require a lot of fine-tuning.

Gillen is most familiar to HBO fans as the slimy politician Thomas Carcetti on The Wire; he recently appeared in the John Cena vehicle 12 Rounds.

Over on broadcast TV, The Live Feed reports that Melina Kanakaredes has decided to move on from CSI: NY. In a statement, Kanakaredes said,

“”I made some amazing and lifelong friendships during my six seasons on CSI: NY, and I will treasure them forever!”

The actress has thrived on the spinoff for six seasons; the timing of her departure may be linked to the show’s move to Fridays, and her recent role as Athena in the high-profile Percy Jackson & the Olympians: The Lightning Thief. According to reports, Sela Ward (House) is among the lead contenders fill in and star opposite Gary Sinise in season seven.